Microtransponder Inc. raked in $53 million in an oversubscribed series E round that exceeded its best previous fundraising by nearly 500% and brought the company’s total funds raised to date to $93 million. The new money will be used to commercialize the Vivistim paired VNS system, which received premarket approval in 2021 as what the FDA called the “first stroke rehabilitation option using vagus nerve stimulation.”